Project design

composite products and steel products

In order to get a correct design (and thus price), the constructions must be optimized correctly. We have extensive experience from numerous projects and strongly suggest you to contact us for help with your project.

Basic coating/priming

Scandinavian WeldTech AB normally coat beams and columns according to SS-EN ISO 12944. The surfaces usually coated are those that remain visible after finished assembly.

Normally, SWT perform most of the coating; however, the final layer usually remains and is expected to be done by the customer after the finished assembly.

Please view the quotation/order confirmation for clarification of the conditions in your project.

Add-on for AutoCad 2D

The AutoCad 2D add-on (in Swedish, Danish or Norwegian) is meant as a help to those who want to draw SWT products correctly.

After installation you will get a new menu named SWT, under which the products are located.

Choose the desired product.

After clicking on “SWT-balken”, you will get this icon menu. Choose the desired beam dimension in the left list. The column is pasted as a block into your drawing.

After clicking on “SWT-pelare rund” (a circular SWT column), you will get this icon menu. Choose the desired beam dimension in the left list. The column is pasted as a block into your drawing.

Assembly

General guidelines regarding all lifts

Please note that this document is only meant as advice to the manager at the construction site. Scandinavian WeldTech should not be held liable for how the actual lift is performed – it is the responsibility of the manager at the site to make sure that the lifting is done correctly and in a safe way.

Please check all lift straps and other equipment before each lift, and make sure that they have sufficient capacity. Worn or incorrect tools must not be used.

Important: Never stand beneath a raised beam or column!

Lifting beams with a crane

The beams are best lifted, one by one, with chains and closable hooks. The angle between the two chains must not exceed 60°.

The beams must be lifted one by one and the chains should be fastened in the two marked stays on the top of the beam. It’s possible to attach the hooks directly to the stays or, alternatively, chains could be looped through the stays and then connected by both ends to their respective hook.

Important: Do not use textile straps. They can be damaged by sharp edges and may break.

The columns are best lifted using the steel loop placed near the centre of the top plate. Use textile straps, and make sure to use long enough straps so that they can be detached after the lift without having to use a ladder.

Place the column on the column foot (a foot plate or underlying column as appropriate) and fixate it using a SWT support ring and struts of your choice. When the column is supported, lower the hook and detach the straps.

Assembling the structural frame

The column foot plate The bottom column is mounted on a separate foot plate. It consists of a steel plate which distributes the vertical forces, and a round steel core for mounting the column.

It is suggested to mount the foot plate in a groove in the base plate, using a chemical anchor and grouting. Alternatively, it is possible to cast welding plates directly in the base slabs and then weld the steel cores to the plates on site.

Mounting the column The columns are mounted on the foot plates or underlying columns. When supporting the columns with SWT’s support rings it is important to take into account that the joint to the column foot can be viewed as a free (pivot) joint, and that the loads can be high.

The columns must be aligned vertically, something that should be controlled before continued assembly. It is also important to ensure that contact between the column steel cores exists.

There should be a gap between the outer column pipe and the underlying footplate or floor slab. This ensures that the upcoming casting will work properly.

Mounting the beam Put the beams in position on the intended supports. Please note the order of assembly and position of the markings, as can be seen in the drawings supplied by SWT.

Center the beams and secure them according to instructions on the drawings, e.g. by welding or bolting.

Whether it’s necessary to prop the beam is evident from the drawings. Pre-stressed hollow core slabs should not be propped in field.

Make sure that the beam is correctly secured to the supports. It’s also important to check that sufficient support length exists for the floor slabs before the slabs are mounted, especially on short supports.

Mounting the floor slabs If possible, the beams should be loaded symmetrically along their length. For single-sided support, the beams must be secured to their supports with enough strength to withstand the torsion movement. Propping the beams at the supports could help.

For the beam to interact with the side concrete it’s necessary to lay down cross-reinforcement steels before the floors are cast. These reinforcement steels are delivered with the beams, and are placed in the upper holes of the beam, cc 150 mm, before the casting. SWT does not include the reinforcement steels for the floor slab anchorage.

Aids for the assembly

Scandinavian WeldTech has developed several tools to aid in the assembly of our structural frames.

Composite column: Loop for lifting Each column has a steel loop intended for lifts attached at the top, close to the core. The central placement means that the column will hang almost vertically, which facilitates the placement of the column on the underlying SWT-product.

Composite beam: Marked stays for lifting Every composite beam has two marked stays at the top. They are meant to facilitate the lifting, which is suitably done with chains and hooks. The beams should be lifted one by one.